Enable trunk superlinter (clang-tidy & more)

[dapirian]

I know this project is kind of old, but figured I'd level up the automated code-checking situation here. This PR turns on the trunk superlinter, that runs clang-tidy, which is otherwise quite difficult to run in a useful way. Overall there were 7 linters, autoformatters, and security tools applicable to the tech in plutil that trunk can run.

If the maintainers are interested, the next step (which I can do) would be enabling running trunk check as a CI job, which can be setup to grandfather in preexisting issues, as well as annotate PRs with the issues it finds. Developers can use the trunk vscode extension or trunk cli to see issues locally before pushing a PR as well.

---